Experimental quantum teleportation of propagating microwaves

Phys.org  January 4, 2022 Recent breakthroughs in quantum computation with superconducting circuits trigger a demand for quantum communication channels between spatially separated superconducting processors operating at microwave frequencies. An international team of researchers (Germany, Austria) demonstrated the unconditional quantum teleportation of propagating coherent microwave states by exploiting two-mode squeezing and analog feedforward over a macroscopic distance of d = 0.42 m. They achieved a teleportation fidelity of F = 0.689 ± 0.004, exceeding the asymptotic no-cloning threshold. Thus, the quantum nature of the teleported states is preserved, opening the avenue toward unconditional security in microwave quantum communication. As their principal teleportation […]

Researchers achieve sustained, high-fidelity quantum teleportation

Phys.org  December 29, 2020 An international team of researchers (USA – Caltech, Fermi National Accelerator Laboratory, industry, Harvard University, Canada) used fiber-coupled devices, including state-of-the-art low-noise superconducting nanowire single-photon detectors and off-the-shelf optics to achieve conditional quantum teleportation of time-bin qubits at the telecommunication wavelength of 1536.5 nm. They measured teleportation fidelities that are consistent with an analytical model of their system, which includes realistic imperfections. To demonstrate the compatibility of the setup with deployed quantum networks, they teleported qubits over 22 km of single-mode fiber while transmitting qubits over an additional 22 km of fiber. Their systems, which are […]

Quantum teleportation moves into the third dimension

Physics World  August 7, 2019 All demonstrations of teleportation to date were limited to a two-dimensional subspace−so-called qubit−of the quantized multiple levels of the quantum systems. In general, a quantum particle can naturally possess not only multiple degrees of freedom, but also, many degrees of freedom can have high quantum number beyond the simplified two-level subspace. Making use of multiport beam-splitters and ancillary single photons, an international team of researchers (China, Austria) propose a resource-efficient and extendable scheme for teleportation of arbitrarily high-dimensional photonic quantum states. Experimentally they have demonstrated teleportation of a qutrit, which is equivalent to a spin-1 […]

Researchers teleport information within a diamond

EurekAlert  June 28, 2019 Researchers in Japan have demonstrated quantum state transfer of photon polarization into a carbon isotope nuclear spin coupled to a nitrogen-vacancy center in diamond based on photon-electron Bell state measurement by photon absorption. The carbon spin is first entangled with the electron spin, which is then permitted to absorb a photon into a spin-orbit correlated eigenstate. Detection of the electron after relaxation into the spin ground state allows post-selected transfer of arbitrary photon polarization into the carbon memory. The study has big implications for quantum information technology…read more. Open Access TECHNICAL ARTICLE 

Physicists ‘teleport’ logic operation between separated ions

Science Daily  May 30, 2019 Teleportation of quantum data has been demonstrated previously with ions and a variety of other quantum systems. Now a team of researchers in the US (NIST, University of Colorado) teleported a quantum controlled-NOT (CNOT) logic operation, or logic gate, between two beryllium ion qubits located more than 340 micrometers apart in separate zones of an ion trap, a distance that rules out any substantial direct interaction. A “messenger” pair of entangled magnesium ions is used to transfer information between the beryllium ions (infographic ). They found that its teleported CNOT process entangled the two magnesium ions […]

Researchers demonstrate teleportation using on-demand photons from quantum dots

Phys.org  December 17, 2018 Despite recent advances, the exploitation of deterministic quantum light sources in push-button quantum teleportation schemes remains a major open challenge. An international team of researchers (Austria, Italy, Sweden) has shown that photon pairs generated on demand by a GaAs quantum dot can be used to implement a teleportation protocol whose fidelity violates the classical limit (by more than 5 SDs) for arbitrary input states. They developed a theoretical framework that matches the experimental observations and that defines the degree of entanglement and indistinguishability needed to overcome the classical limit independently of the input state. The results […]

Scientists ‘teleport’ a quantum gate

Science Daily  September 5, 2018 Modularity is used in constructing a large-scale quantum processor because of the errors and noise that are inherent in real-world quantum systems. An essential tool for universal quantum computation is the teleportation of an entangling quantum gate. Researchers at Yale University demonstrated the teleportation of a controlled-NOT (CNOT) gate, took a crucial step towards implementing robust, error-correctable modules by enacting the gate between two logical qubits, encoding quantum information redundantly. By using such an error-correctable encoding, their teleported gate achieves a process fidelity of 79 per cent. Teleported gates have implications for fault-tolerant quantum computation, […]